Revelation 4:1 After these things I looked, and behold, a door standing open in heaven. And the first voice which I heard was like a trumpet speaking with me, saying, “Come up here, and I will show you things which must take place after this.”
2 Immediately I was in the Spirit; and behold, a throne set in heaven, and One sat on the throne.
After these things. What things? The things of the church or the completion of the church age, John heard the voice of God likened to a trumpet saying come up here. Immediately John is caught up to heaven in the Spirit. The church is no more spoken of until the end of Revelation. The events after the church is gone will be God pouring out His wrath upon a Christ rejecting world. With the church now in heaven, the judgements will begin (chapter 6-19). God has not appointed His church to His wrath. We also see here, that God is on the throne still. Everything is in His control and will go down according to His plan. Come LORD Jesus!